The present invention relates to a method of detaching a traveling fiber web from two endless rotating wire belts between which the web is being formed from a fiber suspension. The invention also relates to an apparatus for carrying out this method.
U.S. Pat. No. 5,019,214 discloses forming a fiber web, preferably a paper web, from a fiber suspension in a twin-wire former. In that case the fiber web is detached from the two endless rotating wire belts of the twin-wire former at the end of the twin-wire zone. First, one traveling wire belt, the upper wire belt in the patent, is removed from the web. The web continues to travel with the other, lower, wire belt, for instance around the circumference of a guide roll or on a so-called separation suction box which rests against the bottom of the lower wire. The other wire belt then travels, together with the web lying on top of it, over a wire suction roll, and then the web is transferred to a felt belt by means of a so-called suction pick-up roll. The felt belt conducts the fiber web into a press section for further removal of water.
The known method and the known apparatus have proven their value in practice. Improvements are desirable, particularly with respect to obtaining an even better quality of the final fiber web, particularly a paper web. Furthermore, continuous attempts are made to obtain a simpler and more compact construction for the twin-wire former and of the following press section and to increase the water removal abilities of the wire suction roll and of the press section so that greater dryness of the web is obtained as it leaves the press section.